I realize the author is probably just having fun, but if a few modern features added to this and I would probably try it.
Multi cursor, a little terminal window, some way to do code hints or intelligence. This would be a dream boat lol
I started this just for the lulz, but now I've got:
copy/paste/undo
multiple cursors
debuggers
syntax highlighting (even nested languages with jetbrains style comments!)
find-in-files
integrated documentation
integrated git client (roughly modeled after lazygit)
spell checking
and tons more that I can't even remember